import java.util.Scanner;
/**
 * Created with IntelliJ IDEA.
 * Description:
 * User: 28463
 * Date: 2022—07—13
 * Time: 15:15
 */
public class Demo03 {

        public static void main(String[] args) {
            Scanner in = new Scanner(System.in);
            while (in.hasNext()) {
                String str = in.nextLine();
                String str1 = String.valueOf(str.charAt(0));
                for(int i = 0; i <str.length(); i++) {
                    if(!str1.contains(String.valueOf(str.charAt(i)))) {
                        str1 += str.charAt(i);
                    }
                }
                System.out.println(str1);
            }
        }
}

